Sundials Are Boring, Use Lasers Instead

//Dual steppermotor clock with lasers

// communication with RTC and RTC lib
#include <Wire.h>
#include "RTClib.h"

RTC_DS3231 rtc;

//stepper variables and lib

#include <Stepper.h>
#define STEPS 2038 // the number of steps in one revolution of your motor (28BYJ-48)
Stepper stepper1(STEPS, 8, 10, 9, 11); //minute stepper
Stepper stepper2(STEPS, 4, 6, 5, 7); //hour stepper
int startup = 0; // counter for resetting stepperposition
int Led = 13; // define LED pin
int buttonpin = 3; // define photo interrupter signal pin
int val; //define a numeric variable

// Startup, RTC check, calibration of steppers, adjusting steppers to current time
void setup()
{

  // RTC Time input
  Serial.begin(9600);
  delay(3000); // wait for console opening
  if (! rtc.begin()) {
    Serial.println("Couldn't find RTC");
    while (1);
  }

  //Steppermotor calibration
  pinMode(Led, OUTPUT); // LED pin as output
  pinMode(buttonpin, INPUT); //photo interrupter pin as input

  // minute stepper calibration
  do {
    val = digitalRead(buttonpin); //read the value of the photointerrupter
    if (val == HIGH) // turn on LED when photointerrupter is blocked
    {
      stepper1.setSpeed(10); // 10 rpm
      stepper1.step(-50); // 50 steps from resetpoint
      startup = startup + 1;
      digitalWrite(Led, HIGH);
    }
    else
    {
      stepper1.setSpeed(5); // 5 rpm
      stepper1.step(1); // stepping towards photointerrupter
      digitalWrite(Led, LOW);
    }
  } while (startup < 2);
  // hour stepper calibration
  do {
    val = digitalRead(buttonpin); //read the value of the photointerrupter
    if (val == HIGH) // turn on LED when photointerrupter is blocked
    {
      stepper2.setSpeed(10); // 10 rpm
      stepper2.step(50); // 50 steps from resetpoint
      startup = startup + 1;
      digitalWrite(Led, HIGH);
    }
    else
    {
      stepper2.setSpeed(5); // 5 rpm
      stepper2.step(-1); // stepping towards photointerrupter
      digitalWrite(Led, LOW);
    }
  } while (startup < 4);
  startup = 0;
  digitalWrite(Led, LOW);


  // time check with RTC
  DateTime now = rtc.now();

  // adjusting steppers to current time
  stepper1.setSpeed(10); // 10 rpm
  stepper1.step(- now.minute() * 15); // adjust minute stepper

  stepper2.setSpeed(10); // 10 rpm
  if (now.hour() >= 12) {
    stepper2.step((now.hour() - 12) * 60 + now.minute()); // adjust hour stepper
  }
  else if (now.hour() <= 12) {
    stepper2.step(now.hour() * 60 + now.minute()); //  adjust hour stepper
  }

  // 90-96 control for testing purpose only
  Serial.print("Time ");
  Serial.print(now.hour());
  Serial.print(":");
  Serial.print(now.minute());
  Serial.print(":");
  Serial.print(now.second());
  Serial.println("");

}

// startup loop with 12:00:00, 0:00:00 and hourly resets of stepper. Stepper minute increment
void loop()
{

  // update of RTC time
  DateTime now = rtc.now();

  // Reset minute and hour stepper at 12:00:00
  if (now.hour() == 12 && now.minute() == 00 && now.second() == 00) {

    // minute stepper calibration
    do {
      val = digitalRead(buttonpin); //read the value of the photointerrupter
      if (val == HIGH) // turn on LED when photointerrupter is blocked
      {
        stepper1.setSpeed(10); // 10 rpm
        stepper1.step(-50); // 50 steps from resetpoint
        startup = startup + 1;
        digitalWrite(Led, HIGH);
      }
      else
      {
        stepper1.setSpeed(5); // 5 rpm
        stepper1.step(1); // stepping towards photointerrupter
        digitalWrite(Led, LOW);
      }
    } while (startup < 2);
    // hour stepper calibration
    do {
      val = digitalRead(buttonpin); //read the value of the photointerrupter
      if (val == HIGH) // turn on LED when photointerrupter is blocked
      {
        stepper2.setSpeed(10); // 10 rpm
        stepper2.step(50); // 50 steps from resetpoint
        startup = startup + 1;
        digitalWrite(Led, HIGH);
      }
      else
      {
        stepper2.setSpeed(5); // 5 rpm
        stepper2.step(-1); // stepping towards photointerrupter
        digitalWrite(Led, LOW);
      }
    } while (startup < 4);
    startup = 0;
    digitalWrite(Led, LOW);

    // delay so that event does not repeat
    delay(1000);
  }

  // stepper motor reset at 0:00:00
  if (now.hour() == 00 && now.minute() == 00 && now.second() == 00) {

    // minute stepper calibration
    do {
      val = digitalRead(buttonpin); //read the value of the photointerrupter
      if (val == HIGH) // turn on LED when photointerrupter is blocked
      {
        stepper1.setSpeed(10); // 10 rpm
        stepper1.step(-50); // 50 steps from resetpoint
        startup = startup + 1;
        digitalWrite(Led, HIGH);
      }
      else
      {
        stepper1.setSpeed(5); // 5 rpm
        stepper1.step(1); // stepping towards photointerrupter
        digitalWrite(Led, LOW);
      }
    } while (startup < 2);
    // hour stepper calibration
    do {
      val = digitalRead(buttonpin); //read the value of the photointerrupter
      if (val == HIGH) // turn on LED when photointerrupter is blocked
      {
        stepper2.setSpeed(10); // 10 rpm
        stepper2.step(50); // 50 steps from resetpoint
        startup = startup + 1;
        digitalWrite(Led, HIGH);
      }
      else
      {
        stepper2.setSpeed(5); // 5 rpm
        stepper2.step(-1); // stepping towards photointerrupter
        digitalWrite(Led, LOW);
      }
    } while (startup < 4);
    startup = 0;
    digitalWrite(Led, LOW);

    // delay so that event does not repeat
    delay(1000);

  }

  // hourly minute stepper reset

  if (now.minute() == 0 && now.second() == 0 ) {

    do {
      val = digitalRead(buttonpin); //read the value of the photointerrupter
      if (val == HIGH) // turn on LED when photointerrupter is blocked
      {
        stepper1.setSpeed(10); // 10 rpm
        stepper1.step(-50); // 50 steps from resetpoint
        startup = startup + 1;
        digitalWrite(Led, HIGH);
      }
      else
      {
        stepper1.setSpeed(5); // 5 rpm
        stepper1.step(1); // stepping towards photointerrupter
        digitalWrite(Led, LOW);
      }
    } while (startup < 2);

    startup = 0;
    digitalWrite(Led, LOW);

    // delay so that event does nor repeat
    delay(1000);

  }

  // minute stepper one minute increment, hourstepper one minute increment

  if (now.second() == 59) {

    stepper1.setSpeed(10); // 1 rpm
    stepper1.step(-15); // 15 stepps equals one minute

    stepper2.setSpeed(10); // 10 rpm
    stepper2.step(1); // 1 stepp equals one minute on hour steppper

    // delay so that event does not repeat
    delay(1000);

  }

  digitalWrite(Led, LOW);

}